Cita APA (7th ed.)
Steinbeck, J. (1991). The grapes of wrath. Reader's Digest Association.
Cita Chicago (17th ed.)
Steinbeck, John. The Grapes of Wrath. Pleasantville, N.Y.: Reader's Digest Association, 1991.
Cita MLA (9th ed.)
Steinbeck, John. The Grapes of Wrath. Reader's Digest Association, 1991.
Atenció: Aquestes cites poden no estar 100% correctes.